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Human Impact on the Atmosphere

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Title: Human Impact on the Atmosphere


1
Human Impact on the Atmosphere
2
Pollution Thorpe, Gary S., M.S., (2002).
Barrons How to prepare for the AP Environmental
Science Advanced Placement Exam
  • The term Smog (smoke and fog) was first used in
    1905 to describe sulfur dioxide emission
  • In 1952, severe pollution took the lives of 5000
    people in London
  • It isnt pollution thats harming the
    environment. Its the impurities in our air and
    water that are doing it.

    Former U.S. Vice President Dan Quayle

www.aqmd.gov/pubinfo/ 97annual.html
3
TheCleanAirAct
  • Congress found
  • Most people now live in urban areas
  • Growth results in air pollution
  • Air pollution endangers living things
  • It decided
  • Prevention and control at the source was
    appropriate
  • Such efforts are the responsibility of states
    and local authorities
  • Federal funds and leadership are essential for
    the development of effective programs

4
Clean Air Act
  • Originally signed 1963
  • States controlled standards
  • 1970 Uniform Standards by Federal Govt.
  • Criteria Pollutants
  • Primary Human health risk
  • Secondary Protect materials, crops, climate,
    visibility, personal comfort

5
Clean Air Act
  • 1990 version
  • Acid rain, urban smog, toxic air pollutants,
    ozone depletion, marketing pollution rights,
    VOCs
  • 1997 version
  • Reduced ambient ozone levels
  • Cost 15 billion/year -gt save 15,000 lives
  • Reduce bronchitis cases by 60,000 per year
  • Reduce hospital respiratory admission 9000/year

6
Clean Air Act
  • President George W. Bush signed rules amending
    Clean Air Act that allowed power plants and other
    industries to increase pollution significantly
    without adopting control measures

7
http//www.cnn.com/2003/LAW/12/24/bush.clean.air.a
p/index.html
Appeals court blocks Bush clean air
changes Wednesday, December 24, 2003 Posted 210
PM EST (1910 GMT)
  • WASHINGTON (AP) -- A federal appeals court on
    Wednesday blocked new Bush administration changes
    to the Clean Air Act from going into effect the
    next day, in a challenge from state attorneys
    general and cities that argued they would harm
    the environment and public health.

8
Clean Air Act http//www.epa.gov/air/oaq_caa.html
  • Title I - Air Pollution Prevention and Control
  • Part A - Air Quality and Emission Limitations
  • Part B - Ozone Protection (replaced by Title VI)
  • Part C - Prevention of Significant Deterioration
    of Air Quality
  • Part D - Plan Requirements for Nonattainment
    Areas
  • Title II - Emission Standards for Moving Sources
  • Part A - Motor Vehicle Emission and Fuel
    Standards
  • Part B - Aircraft Emission Standards
  • Part C - Clean Fuel Vehicles
  • Title III - General
  • Title IV - Acid Deposition Control
  • Title V - Permits
  • Title VI - Stratospheric Ozone Protection

9
Outdoor Air Pollution
10
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11
Major Sources of Primary Pollutants
  • Stationary Sources
  • Combustion of fuels for power and heat Power
    Plants
  • Other burning such as Wood crop burning or
    forest fires
  • Industrial/ commercial processes
  • Solvents and aerosols
  • Mobile Sources
  • Highway cars, trucks, buses and motorcycles
  • Off-highway aircraft, boats, locomotives, farm
    equipment, RVs, construction machinery, and lawn
    mowers

12
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13
54 million metric tons from mobile sources in 1990
14
Human Impact on Atmosphere
  • Burning Fossil Fuels
  • Using Nitrogen fertilizers and burning fossil
    fuels
  • Refining petroleum and burning fossil fuels
  • Manufacturing
  • Adds CO2 and O3 to troposphere
  • Global Warming
  • Altering Climates
  • Produces Acid Rain
  • Releases NO, NO2, N2O, and NH3 into troposphere
  • Produces acid rain
  • Releases SO2 into troposphere
  • Releases toxic heavy metals (Pb, Cd, and As) into
    troposphere

www.dr4.cnrs.fr/gif-2000/ air/products.html
15
Criteria Air Pollutants
  • EPA uses six "criteria pollutants" as indicators
    of air quality
  • Nitrogen Dioxide NO2
  • Ozone ground level O3
  • Carbon monoxide CO
  • Lead Pb
  • Particulate Matter PM10 (PM 2.5)
  • Sulfur Dioxide SO2
  • Volatile Organic Compounds (VOCs)
  • EPA established for each concentrations above
    which adverse effects on health may occur

16
Nitrogen Dioxide (NO2)
  • Properties reddish brown gas, formed as fuel
    burnt in car, strong oxidizing agent, forms
    Nitric acid in air
  • Effects acid rain, lung and heart problems,
    decreased visibility (yellow haze), suppresses
    plant growth
  • Sources fossil fuels combustion, power plants,
    forest fires, volcanoes, bacteria in soil
  • Class Nitrogen oxides (NOx)
  • EPA Standard 0.053 ppm

17
Mobile Source Emissions Nitrogen Oxides
18
Ozone (O3)
  • Properties colorless, unpleasant odor, major
    part of photochemical smog
  • Effects lung irritant, damages plants, rubber,
    fabric, eyes,
  • Sources Created by sunlight acting on NOx and
    VOC , photocopiers, cars, industry, gas vapors,
    chemical solvents, incomplete fuel combustion
    products
  • Class photochemical oxidants

19
Ozone (O3)
  • 10,000 to 15,000 people in US admitted to
    hospitals each year due to ozone-related illness
  • Children more susceptible
  • Airways narrower
  • More time spent outdoors

20
Mobile Source Emissions Hydrocarbons
Precursors to Ozone
21
Carbon Monoxide (CO)
  • Properties colorless, odorless, heavier than
    air, 0.0036 of atmosphere
  • Effects binds tighter to Hb than O2, mental
    functions and visual acuity, even at low levels
  • Sources incomplete combustion of fossil fuels 60
    - 95 from auto exhaust
  • Class carbon oxides (CO2, CO)
  • EPA Standard 9 ppm
  • 5.5 billion tons enter atmosphere/year

22
Mobile Source Emissions - CO
23
Lead (Pb)
  • Properties grayish metal
  • Effects accumulates in tissue affects kidneys,
    liver and nervous system (children most
    susceptible) mental retardation possible
    carcinogen 20 of inner city kids have high
  • Sources particulates, smelters, batteries
  • Class toxic or heavy metals
  • EPA Standard 1.5 ug/m3
  • 2 million tons enter atmosphere/year

24
Suspended Particulate Matter (PM10)
  • Properties particles suspended in air (lt10 um)
  • Effects lung damage, mutagenic, carcinogenic,
    teratogenic
  • Sources burning coal or diesel, volcanoes,
    factories, unpaved roads, plowing, lint, pollen,
    spores, burning fields
  • Class SPM dust, soot, asbestos, lead, PCBs,
    dioxins, pesticides
  • EPA Standard 50 ug/m3 (annual mean)

25
Mobile Source Emissions Fine Particulate Matter
(PM2.5)
26
Sulfur Dioxide (SO2)
  • Properties colorless gas with irritating odor
  • Effects produces acid rain (H2SO4), breathing
    difficulties, eutrophication due to sulfate
    formation, lichen and moss are indicators
  • Sources burning high sulfur coal or oil,
    smelting or metals, paper manufacture
  • Class sulfur oxides
  • EPA Standard 0.3 ppm (annual mean)
  • Combines with water and NH4 to increase soil
    fertility

27
VOCs (Volatile Organic Compounds)
  • Properties organic compounds (hydrocarbons) that
    evaporate easily, usually aromatic
  • Effects eye and respiratory irritants
    carcinogenic liver, CNS, or kidney damage
    damages plants lowered visibility due to brown
    haze global warming
  • Sources vehicles (largest source), evaporation
    of solvents or fossil fuels, aerosols, paint
    thinners, dry cleaning
  • Class HAPs (Hazardous Air Pollutants)
  • Methane
  • Benzene
  • Chlorofluorocarbons (CFCs), etc.
  • Concentrations indoors up to 1000x outdoors
  • 600 million tons of CFCs

28
Other Air Pollutants
  • Carbon dioxide
  • ChloroFluoroCarbons
  • Formaldehyde
  • Benzene
  • Asbestos
  • Manganese
  • Dioxins
  • Cadmium
  • Others not yet fully characterized

29
Formation Intensity
  • Factors
  • Local climate (inversions, air pressure,
    temperature, humidity)
  • Topography (hills and mountains)
  • Population density
  • Amount of industry
  • Fuels used by population and industry for
    heating, manufacturing, transportation, power
  • Weather rain, snow,wind
  • Buildings (slow wind speed)
  • Mass transit used
  • Economics

30
Thermal Inversion
31
Smog Forms
...when polluted air is stagnant (weather
conditions, geographic location)
Los Angeles, CA
32
Primary Pollutants
CO
CO2
Secondary Pollutants
SO2
NO
NO2
SO3
Most hydrocarbons
HNO3
H2SO4
Most suspended particles
H2O2
O3
PANs
and
salts
Most
Natural
Sources
Stationary
Mobile
33
Photochemical Smog
UV radiation H2O O2
Primary Pollutants NO2 Hydrocarbons
Secondary Pollutants HNO3 O3 nitric
acid ozone Photochemical Smog
Auto Emissions
34
Solar radiation
Photochemical Smog
Ultraviolet radiation
NO Nitric oxide
O2 Molecular oxygen
O Atomic oxygen
NO2 Nitrogen dioxide
H2O Water
Hydrocarbons
PANs Peroxyacyl nitrates
Aldehydes (e.g., formaldehyde)
O3 Ozone
HNO3 Nitric acid
P h o t o c h e m i c a l S m o g
35
Indoor Air Pollution
36
Why is indoor air quality important?
  • 70 to 90 of time spent indoors, mostly at home
  • Many significant pollution sources in the home
    (e.g. gas cookers, paints and glues)
  • Personal exposure to many common pollutants is
    driven by indoor exposure
  • Especially important for susceptible groups
    e.g. the sick, old and very young

37
Exposure
  • Time spent in various environments in US and
    less-developed countries

38
House of Commons Select Committee Enquiry on
Indoor Air Pollution (1991)
  • There is evidence that 3 million people have
    asthma in the UK and this is increasing by 5
    per annum.
  • Overall there appears to be a worryingly large
    number of health problems which could be
    connected with indoor pollution and which affect
    very large numbers of the population.
  • The Committee recommends that the Government
    develop guidelines and codes of practice for
    indoor air quality in buildings which
    specifically identify exposure limits for an
    extended list of pollutants

39
Sources of Indoor Air Pollutants
  • Building materials
  • Furniture
  • Furnishings and fabrics
  • Glues
  • Cleaning products
  • Other consumer products
  • Combustion appliances (cookers and heaters)
  • Open fires
  • Tobacco smoking
  • Cooking
  • House dust mites, bacteria and moulds
  • Outdoor air

40
Important Indoor Air pollutants
  • Nitrogen dioxide
  • Carbon monoxide
  • Formaldehyde
  • Volatile Organic Compounds (VOCs)
  • House dust mites (and other allergens, e.g. from
    pets)
  • Environmental tobacco smoke
  • Fine particles
  • Chlorinated organic compounds (e.g. pesticides)
  • Asbestos and man-made mineral fibres
  • Radon

41
Health Effects
  • Nitrogen dioxide
  • Respiratory irritant
  • Elevated risk of respiratory illness in children,
    perhaps resulting from increased susceptibility
    to respiratory infection inconsistent evidence
    for effects in adults
  • Concentrations in kitchens can readily exceed WHO
    and EPA standards

42
Health Effects
  • Carbon monoxide
  • An asphyxiant and toxicant
  • Hazard of acute intoxication, mostly from
    malfunctioning fuel-burning appliances and
    inadequate or blocked fumes
  • Possibility of chronic effects of long-term
    exposure to non- lethal concentrations,
    particularly amongst susceptible groups

43
Health Effects
  • Formaldehyde
  • Sensory and respiratory irritant and sensitizer
  • Possible increased risk of asthma and chronic
    bronchitis in children at higher exposure levels
  • Individual differences in sensory and other
    transient responses
  • Caution over rising indoor concentrations

44
Health Effects
  • Volatile Organic Compounds (VOCs)
  • Occur in complex and variable mixtures
  • Main health effects relate to comfort and
    well-being, but benzene (and other VOCs) are
    carcinogenic
  • Concern about possible role of VOCs in the
    aetiology of multiple chemical sensitivity also
    implicated in sick building syndrome

45
Health Effects
  • House dust mites
  • House dust mites produce Der p1 allergen, a
    potent sensitizer
  • Good evidence of increased risk of sensitization
    with increasing allergen exposure, but this does
    not necessarily lead to asthma
  • Small reductions in exposure will not necessarily
    lead to reduced incidence and/or symptoms
  • Indoor humidity is important

46
Health Effects
  • Fungi and bacteria
  • Dampness and mould-growth linked to self-reported
    respiratory conditions, but little convincing
    evidence for association between measured
    airborne fungi and respiratory disease
  • Insufficient data to relate exposure to
    (non-pathogenic) bacteria to health effects in
    the indoor environment

47
Health Effects
  • Environmental tobacco smoke (ETS)
  • Sudden infant death syndrome
  • Lower respiratory tract illness
  • Middle ear disease
  • Asthma
  • 12 million children exposed to secondhand smoke
    in homes

48
Health Effects
  • Fine particles
  • Consistent evidence that exposure to small
    airborne particles (e.g. PM10) in ambient air can
    impact on human health mechanisms uncertain
  • Chronic Obstructive Pulmonary Disease and
    Cardiovascular Disease patients and asthmatics
    probably at extra risk
  • Relative importance of indoor sources is unknown

49
Health Effects
  • Radon
  • Can cause lung cancer
  • Estimated that 7,000 to 30,000 Americans die each
    year from radon-induced lung cancer
  • Only smoking causes more lung cancer deaths
  • Smokers more at risk than non-smokers

50
Radon Risk Non-Smoker
If you are a former smoker, your risk may be
higher
51
Radon Risk Smoker
If you are a former smoker, your risk may be lower
52
Radon
  • 55 of our exposure to radiation comes from radon
  • colorless, tasteless, odorless gas
  • formed from the decay of uranium
  • found in nearly all soils
  • levels vary

53
(From http//www.epa.gov/iaq/radon/zonemap.html)
Zone pCi/L 1 gt4 2 2 - 4
3 lt2
54
Radon How it Enters Buildings
  • Cracks in solid floors
  • Construction joints
  • Cracks in walls
  • Gaps in suspended floors
  • Gaps around service pipes
  • Cavities inside walls
  • The water supply

http//www.epa.gov/iaq/radon/pubs/citguide.htmlho
wdoes
55
Radon Reducing the Risks
  • Sealing cracks in floors and walls
  • Simple systems using pipes and fans
  • More information http//www.epa.gov/iaq/radon/pub
    s/consguid.htmlreductiontech

56
  • Sick Building Syndrome (SBS)
  • vs
  • Building Related Illness (BRI)

57
Sick Building Syndrome
  • A persistent set of symptoms in gt 20 population
  • Causes(s) not known or recognizable
  • Complaints/Symptoms relieved after exiting
    building

58
Complaints/Symptoms
  • Headaches
  • Fatigue
  • Reduced Mentation
  • Irritability
  • Eye, nose or throat irritation
  • Dry Skin
  • Nasal Congestion
  • Difficulty Breathing
  • Nose Bleeds
  • Nausea

59
Building Related Illness
  • Clinically Recognized Disease
  • Exposure to indoor air pollutants
  • Recognizable Causes

60
Clinically Recognized Diseases
  • Pontiac Fever Legionella spp.
  • Legionnaire's Disease
  • Hypersensitivity Pneumonitis
  • Humidifier Fever
  • Asthma
  • Allergy
  • Respiratory Disease
  • Chronic Obstructive Pulmonary Disease

61
Ventilation
62
Movement of Air Into / Out of Homes
  • Amount of air available to dilute pollutants
  • important indicator of the likely contaminant
    concentration
  • Indoor air can mix with outside air by three
    mechanisms
  • infiltration
  • natural ventilation
  • forced ventilation

63
Movement of Air Into / Out of Homes
  • Infiltration
  • natural air exchange that occurs between a
    building and its environment when the doors and
    windows are closed
  • leakage through holes or openings in the building
    envelope
  • pressure induced
  • due to pressure differentials inside and outside
    of the building
  • especially important with cracks and other
    openings in wall

64
Movement of Air Into / Out of Homes
  • Infiltration
  • Temperature induced (stack effect)
  • driven by air movement through holes in floors,
    ceilings
  • in winter, warm air in a building wants to rise,
    exits through cracks in ceiling and draws in

65
Movement of Air Into / Out of Homes
  • Natural ventilation
  • air exchange that occurs when windows or doors
    are opened to increase air circulation
  • Forced ventilation
  • mechanical air handling systems used to induce
    air exchange using fans and blowers
  • Trade-offs
  • cut infiltration to decrease heating and cooling
    costs vs. indoor air quality problems

66
Movement of Air Into / Out of Homes
  • Infiltration rates
  • Influenced by
  • how fast wind is blowing, pressure differentials
  • temperature differential between inside and
    outside of house
  • location of leaks in building envelope

67
Greenhouse Effect
68
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69
http//royal.okanagan.bc.ca/mpidwirn/atmosphereand
climate/cascade.html
70
Natural Greenhouse Effect
  • With Greenhouse Effect average global temperature
    60 degrees
  • Without it, Earth would be a frigid planet, with
    average temperature around zero degrees
    Fahrenheit

71
Global Warming
Increased Greenhouse Gases in the Troposphere
Excess heat
CO2 CFCs CH4
72
Greenhouse Gases
Carbon dioxide Methane Nitrous oxide Ozone CFCs
Hydrofluorocarbons Perfluorinated carbons Water
vapour
73
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74
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75
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76
Is this increase in temperature natural or ?
77
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78
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79
Measurements made at Mauna Loa, Hawaii elevation
12,000 feet
80
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81
Contribution to Greenhouse Effect
82
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83
Methane
  • Core samples taken from old ocean sediment layers
    have been used to trace back in time the climate
    changes that have occurred over the past tens of
    millions of years
  • short periods of only a few hundred years in the
    geological past when rapid increases of the
    Earth's temperature have occurred superimposed on
    top of the rise and fall of average temperatures
    over the longer term up to 15 degrees centigrade
    warmer than today.

84
Methane
  • Temperatures then fell back to the long term
    trend, the whole rise and fall only lasting a few
    hundred years.
  • The most likely cause of this rapid global
    warming over such a short period is the release
    of methane into the atmosphere.
  • Methane is 60 times more powerful than CO2 as a
    greenhouse gas
  • Methane was released due to breakdown of material
    associated with permafrost

85
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87
Top Greenhouse Gas Emitters
  • 19.1 - United States
  • 9.9 - China
  • 5.1 - Japan
  • 4.3 - Brazil
  • 3.8 - Germany
  • 3.7 - Japan
  • 2.4 - United Kingdom
  • 1.9 - Indonesia
  • 1.7 - Italy

88
What impacts have occurred and are predicted to
occur from global warming?
  • ?

89
Atmosphere Impacts from Global Warming?
  • Weather
  • Ocean currents
  • Sea level
  • Water resources
  • Biodiversity
  • Forests
  • Human health
  • Agriculture
  • Human demographics

90
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91
Direct manifestations
  • Heat waves and periods of unusually warm weather
  • Sea level rise and coastal flooding
  • Glaciers melting
  • Arctic and Antarctic warming with ice shelves
    breaking up
  • Increase severity of weather
  • Zooplankton are dying in the Pacific Ocean

92
Heat wave kills 30, no relief in sight July
27, 1999 http//www
.cnn.com/WEATHER/9907/27/heat.wave.02/index.html

93
Monster iceberg breaks off Antarctic ice shelf
May 10, 2002 http//www
.cnn.com/2002/TECH/space/05/09/iceberg.satellite/i
ndex.html

94
Antarctica
95
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96
If all the ice on Greenland melted, world sea
levels would rise about six metres (20 feet)If
all the ice on the Antarctic continent melted,
sea levels would rise over 70 metres (230
feet)This is unlikely to happen, but small
increases will continue.
97
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99
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100
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101
Possible Consequences
  • Spreading disease
  • Earlier spring arrival
  • Plant and animal range shifts and population
    declines
  • Coral reef bleaching
  • Downpours, heavy snowfalls, and flooding
  • Droughts and fires

102
Global warming may harm human health November
16, 1998 Climatic changes related to global
warming could foster dangerous outbreaks of
cholera, dengue fever and malaria,
http//www.cnn.com/TECH/science/9811/16/clima
te.health.enn/index.html

103
Study Global warming spurs migrations
Thursday, January 2, 2003 Rising global
temperatures that have lured plants into early
bloom and birds to nest earlier in the spring are
altering the ranges and behavior of hundreds of
plant and animal species worldwide, two studies
conclude. http//www.cnn.com/2003/TEC
H/science/01/02/climate.migrations.ap/index.html

104
Report Coral bleaching hits record level May
19, 1999 Global warming has been linked to an
unprecedented episode of coral bleaching in
1998, http//www.cnn.com/NATURE/9905/19/cora
l.bleaching.enn/index.html

105
Vicious cycle Global warming feeds fire
potential November 2, 2000 Global warming may
greatly accelerate the fire cycle in the desert
ecosystem of North America, according to a study
published today in the journal Nature.
Elevated carbon dioxide levels, the result of
increased fossil fuel burning, can alter the
delicate balance of grasses in desert areas, the
report notes. This finding may have major
implications for the biodiversity and health of
desert ecosystems in the western United States.
"This could be a real problem for land
managers," said Stan Smith, a professor of
biology at the University of Nevada in Las Vegas
and lead author of the study.
http//www.cnn.com/2000/NATURE/11/02/global.warmin
g.enn/index.html

106
http//www.soton.ac.uk/engenvir/environment/air/g
reenhouse.problems.html
107
Anomaly difference between actual value and
some mean value in this case the mean is a 30
year average
108
Warmest Years on Record
  • 1981
  • 1983
  • 1987
  • 1988
  • 1989
  • 1990
  • 1991
  • 1994
  • 1995
  • 1996
  • 1997
  • 1998
  • 1999
  • 2000
  • 2001

109
Ozone Hole
110
Understanding Ozone http//royal.okanagan.bc.ca/mp
idwirn/atmosphereandclimate/ozonehole.html
  • Discovered in 1839 by German scientist Christian
    Friedrich Schonbein
  • Pale blue, unstable molecule made of three oxygen
    atoms
  • Vital to life in the stratosphere
  • Harmful to plants and humans in the troposphere
  • Concentration stratosphere ? up to 15 ppm at
    about 25 km
  • Formed when atomic oxygen (O) from higher parts
    of the atmosphere collides with molecular oxygen
    (O2) in the stratosphere
  • UV radiation splits the ozone back to O and O2
    and it can form another ozone molecule

111
http//www-imk.fzk.de/topoz-iii/ataglanz/ozonbild.
html
112
http//www-imk.fzk.de/topoz-iii/ataglanz/ozonzerst
.html
113
The Ozone Hole
  • First discovered in 1985 observations from
    Antarctica extend back into 1950s.
  • Characterized as a rapid depletion of ozone over
    Antarctica during spring.
  • Ozone hole season, Spring (August October)
  • Ozone hole located over mainly over Antarctica.
  • Ozone hole recovers by late December
  • Ozone hole caused by human chemicals (CFCs)
  • Ozone hole not present in early 1970s

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116
science.widener.edu/svb/ atmo_chem/oct15.html
117
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118
Ozone hole stabilizes October 17, 2001 WASHINGTON
(CNN) -- A hole in the Earth's
protective ozone layer
is about the same size as in the past three
years, according to scientists at
the National Oceanic and
Atmospheric Administration, who
predict it will hold steady in the near
future.
Satellite data show the hole
over Antarctica, which allows more
harmful solar radiation to reach
the Earth, peaked this year at about 10
million square miles (26 million square km),
roughly the size of North America.
http//www.cnn.com/2001/TECH/space/10/17/ozone.ho
le.size/index.html
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120
History of Ozone Depletion
  • CFCs developed in 40s and 50s
  • Refrigerants, propellants, fire retardants
  • 1970s CFCs detected in atmosphere.
  • Many of these have long atmospheric lifetimes
    (10s to 100s of years)
  • 1974 Rowland and Molina propose that CFCs can
    destroy ozone in the stratosphere.
  • CFCs broken apart by UV radiation forming
    chlorine which can destroy ozone quickly
  • O3 Cl ? ClO O2 (Catalytic Reaction)
  • ClOO ? ClO2

121
Chlorofluorocarbons or CFCs
  • First produced by General Motors Corporation in
    1928, CFCs were created as a replacement to the
    toxic refrigerant ammonia
  • CFCs have also been used as a propellant in spray
    cans, cleaner for electronics, sterilant for
    hospital equipment, and to produce the bubbles in
    Styrofoam

122
  • CFCs are cheap to produce and very stable
    compounds, lasting up to 200 years in the
    atmosphere
  • Many countries have recently passed laws banning
    nonessential use of these chemicals.
  • Nevertheless, by 1988 some 320,000 metric tons
    of CFCs were used worldwide.

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125
Action of CFCs
  • CFCs created at the Earth's surface drift slowly
    upward to the stratosphere where UV radiation
    from the sun causes their decomposition and the
    release of chlorine
  • Chlorine in turn attacks the molecules of ozone
    converting them into oxygen molecules
  • Cl O3 ClO O2
  • ClO O Cl O2

126
Ultraviolet light hits a chlorofluorocarbon
(CFC) molecule, such as CFCl3, breaking off a
chlorine atom and leaving CFCl2.
Sun
Cl
Cl
Once free, the chlorine atom is off to attack
another ozone molecule and begin the cycle again.
C
Cl
F
UV radiation
Cl
Cl
O
O
A free oxygen atom pulls the oxygen atom off
the chlorine monoxide molecule to form O2.
The chlorine atom attacks an ozone (O3) molecule,
pulling an oxygen atom off it and leaving an
oxygen molecule (O2).
Cl
Cl
O
O
O
O
O
The chlorine atom and the oxygen atom join to
form a chlorine monoxide molecule (ClO)
Cl
O
O
O
127
http//www.clas.ufl.edu/users/dlsmith/Lecture_11.h
tml
128
  • A single chlorine atom removes about 100,000
    ozone molecules before it is taken out of
    operation by other substances

129
Low and Middle Latitudes
  • Current measurements indicate that the amount of
    ozone in the stratosphere of the low and middle
    latitudes has decreased by about 3 with
    estimates that it will decrease by10 by 2025

130
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131
Harmful effects of UV radiation.
  • Skin cancer (ultraviolet radiation can destroy
    acids in DNA)
  • Cataracts and sun burning
  • Suppression of immune systems
  • Adverse impact on crops and animals
  • Reduction in the growth of ocean phytoplankton
  • Cooling of the Earth's stratosphere and possibly
    some surface climatic effect
  • Degradation of paints and plastic material

132
matrix.ucdavis.edu/tumors/tradition/
gallery-ssmm.html
133
www.snec.com.sg/clinical_services/ cataract.asp
134
Conclusion
  • Ozone Depletion Exists and effects certain areas
    of the Earth more than others
  • Currently, one in five North Americans and one in
    two Australians will develop some form of skin
    cancer in their lifetime
  • With a sustained 10 decrease in stratospheric
    ozone, an additional 300,000 non-melanoma and
    4,500 melanoma skin cancers could be expected
    world-wide, according to UNEP estimates.

135
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136
Acid Deposition
137
Measuring Acid Rain
  • Acid rain is measured using a "pH" scale.
  • The lower a substance's pH, the more acidic it
    is.
  • Pure water has a pH of 7.0.
  • Normal rain is slightly acidic and has a pH of
    about 5.6
  • Any rainfall has a pH value less than 5.6 is
    defined as acid rain
  • As of the year 2000, the most acidic rain falling
    in the US has a pH of about 4.3.

138
Two Forms
  • Wet
  • Refers to acid rain, fog, sleet, cloud vapor and
    snow.
  • Dry
  • Refers to acidic gases and particles.

139
Compounds
  • Two main contributers to acid deposition
  • Sulfur Dioxide (SO2)
  • Nitrogen Oxides (NOx)
  • 66 of all sulfur dioxides and 25 of all
    nitrogen oxides comes from electric power
    generation that produces energy by burning fossil
    fuels.

140
  • When gas pollutants e.g. sulphur dioxide,
    nitrogen dioxide dissolve in rain water, various
    acids are formed.

CO2 H2O ? H2CO3 (carbonic acid) SO2
H2O ? H2SO3 (sulphorous acid) NO2 H2O ? HNO2
(nitrous acid) HNO3 (nitric acid)
141
Causes of Acid Rain
  • Sulfur dioxide (SO2) and nitrogen oxides (NOx)
    are the primary causes of acid rain.
  • In the US, About 2/3 of all SO2and 1/4 of all
    NOx comes from electric power generation that
    relies on burning fossil fuels like coal.

142
Acidic Precipitation
Primary Pollutants SO2 NO2
Secondary Pollutants H2SO4 HNO2 sulfuric
acid nitric acid
acidic precipitation
vegetation direct toxicity indirect health effects
water
Fossil fuels Power plants Industrial
emissions Auto emissions
soils leaching of minerals
sediments leaching aluminum
143
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144
Acidic Precipitation
Wind
Transformation to sulfuric acid (H2SO4) and
nitric acid (HNO3)
Windborne ammonia gas and particles of cultivated
soil partially neutralize acids and form dry
sulfate and nitrate salts
Wet acid deposition (droplets of H2SO4 and HNO3
dissolved in rain and snow)
Dry acid deposition (sulfur dioxide gas and
particles of sulfate and nitrate salts)
Sulfur dioxide (SO2) and NO
Nitric oxide (NO)
Acid fog
Farm
Lakes in deep soil high in limestone are buffered
Lakes in shallow soil low in limestone become acid
ic
Ocean
145
BIOL 349 Atmosphere
Fig. 17.10, p. 428
146
Sulphur dioxide emission (1997)
147
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148
Wet Acid Rain
  • Acidic water flows over and through the ground,
    it affects a variety of plants and animals.

149
Dry Acid Rain
  • Dry deposition refers to acidic gases and
    particles.
  • About half of the acidity in theatmosphere falls
    back to earth through dry deposition.
  • The wind blows these acidic
    particles and gases onto buildings, cars, homes,
    and trees.

http//svr1-pek.unep.net/soechina/images/acid.jpg
150
Increased Acidity
  • Dry deposited gases and particles can also be
    washed from trees and other surfaces by
    rainstorms.
  • The runoff water adds those acids to the acid
    rain, making the combination more acidic than the
    falling rain alone.

151
Effects of Acid Rain
  • The strength of the effects depend on many
    factors
  • How acidic the water is
  • The chemistry and buffering capacity of the soils
    involved
  • The types of fish, trees, and other living things
    that rely on the water

152
Effects of Acid Rain
  • Has a variety of effects, including damage to
    forests and soils, fish and other living things,
    materials, and human health.
  • Also reduces how far and how clearly we can see
    through the air, an effect called visibility
    reduction.
  • Effects of acid rain are most clearly seen in the
    aquatic environments
  • Most lakes and streams have a pH between 6 and 8

http//cica.indiana.edu/projects/Biology/movies.ht
ml
153
Buffering Capacity
  • Acid rain primarily affects sensitive bodies of
    water, which are located in watersheds whose
    soils have a limited "buffering capacity
  • Lakes and streams become acidic when the water
    itself and its surrounding soil cannot buffer the
    acid rain enough to neutralize it.

154
  • In areas where buffering capacity is low, acid
    rain also releases aluminum from soils into lakes
    and streams aluminum is highly toxic to many
    species of aquatic organisms.

http//home.earthlink.net/photofish/fish_photos/s
w10_thumb.jpg
155
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156
Effects on Wildlife
  • Generally, the young of most species are more
    sensitive to environmental conditions than
    adults.
  • At pH 5, most fish eggs cannot hatch.
  • At lower pH levels, some adult fish die.
  • Some acid lakes have no fish.

157
Effects on Wildlife
  • Both low pH and increased aluminum levels are
    directly toxic to fish.
  • In addition, low pH and increased aluminum levels
    cause chronic stress that may not kill individual
    fish, but leads to lower body weight and smaller
    size and makes fish less able to compete for food
    and habitat.

158
Acid Rain and Forests
  • Acid rain does not usually kill trees directly.
  • Instead, it is more likely to weaken trees by
    damaging their leaves, limiting the nutrients
    available to them, or exposing them to toxic
    substances slowly released from the soil.

159
Mongolia
Germany
160
Effects of Acid Rain
Great Smoky Mountains, NC
161
Nutrients
  • Acidic water dissolves the nutrients and helpful
    minerals in the soil and then washes them away
    before trees and other plants can use them to
    grow.
  • Acid rain also causes the release of substances
    that are toxic to trees and plants, such as
    aluminum, into the soil.

162
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163
Air Pollution Prevention
164
Specific Air Pollution Treatment Technology
  • Traditional
  • Move factory to remote location
  • Build taller smokestack so wind blows pollution
    elsewhere
  • New
  • Biofiltration vapors pumped through soil where
    microbes degrade
  • High-energy destruction high-voltage electricity
  • Membrane separation diffusion of organic vapors
    through membrane
  • Oxidation High temperature combustor

165
Absorption
166
Adsorption
167
Combustion
168
Cyclone
169
Filtration
170
Electrostatic Precipitator
171
Liquid Scrubber
172
Sulfur Dioxide Control
http//www.apt.lanl.gov/projects/cctc/factsheets/p
uair/adflugasdemo.html
173
Air Pollution Results
174
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175
Comparison of 1970 and 1999 Emissions
176
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177
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178
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179
Number of People Living in Counties with Air
Quality Concentrations Above the Level of the
National Ambient Air Quality Standards (NAAQS) in
1999
180
Trends in Sulfur Dioxide Emissions Following
Implementation of Phase I of the Acid Rain
Program Total State-level Utility SO2 (1980,
1990, 1999)
181
FiftyYearsofAirPollution
Figures are in millions of metric tons per year
182
MobileSourcesThe LastTen Years
VOCs CO NOx PM10 SOx Lead
-3
-8
-10
-24
-29
  • Percent reductions shown are based on estimates
    of tons/year from mobile sources over the 1981 -
    1990 time period

-85
183
Who isAffected byAir Pollution?
63
Over 74 million people are subjected to high
levels of at least one of these pollutants
22
19
9
5
1
Ozone CO NO2 PM10 SO2 Lead
  • Millions of people living in counties with air
    quality that exceeds each NAAQS (1990 data)

184
Milestonesin theControlofAutomotiveEmissions
  • 1952 - Autos linked to air pollution
  • 1963 - Original CAA, PCV valves
  • 1968 - HC CO exhaust controls
  • 1970 - CAA amendments, EPA formed
  • 1971 - Evaporative controls
  • 1972 - First I/M Program
  • 1973 - NOx exhaust controls
  • 1975 - First catalytic converters
  • 1981 - New cars meet statutory limits
  • 1989 - Volatility limits on gasoline
  • 1990 - New CAA Amendments

185
  • 1987 Montreal Protocol CFC emissions should be
    reduced by 50 by the year 2000 (they had been
    increasing 3 per year.)
  • 1990 London amendments production of CFCs,
    CCl4, and halons should cease entirely by 2000.
  • 1992 Copenhagen agreements phase-out
    accelerated to 1996.

186
What is the Kyoto Protocol?
  • How did we get to Kyoto?
  • What are the goals of Kyoto?
  • Is Kyoto enough?

187
Steps to Kyoto
  • 1985 International Council of Scientific Unions
    (Prof. Bert Bolin)
  • Many important economic and social decisions are
    being made today on long term projects, all based
    on the assumption that past climatic data,
    without modification, are a reliable guide to the
    future. This is no longer a good assumption

188
Steps to Kyoto
  • 1988 - Toronto - creation of IPCC
  • warmest summer to date, international meeting in
    Toronto
  • Intergovernmental Panel on Climate Change formed
  • 1990 - First report (FAR)
  • overview of the current science of climate change

189
IPCC
  • IPCC headed by Prof. Bert Bolin
  • 3 working groups
  • Climate Science
  • Climate Impacts
  • Response Strategies
  • 1992 - FAR used in Earth Summit meeting in Rio -
    United Nations Framework Convention on Climate
    Change

190
IPCC
  • 1995 IPCC Second Assessment Report (SAR)
    completed, published in 1996
  • WG I Climate Science
  • WG II Impact, Adaptation and Mitigation
  • WG III Economic and Social Dimensions
  • The balance of evidence suggests a discernible
    human influence on global climate

191
IPCC
  • 1997 Kyoto meeting - binding targets set
  • culmination of a series of meetings since Rio
    (1992)
  • 2001 Bonn - rescuing Kyoto
  • 2001 IPCC Third Assessment Report (TAR)
  • WG I Climate Science
  • WG II Vulnerabilities, Impacts and Adaptation
  • WG III Mitigation

192
IPCC
  • TAR (2001)
  • There is new and stronger evidence that most of
    the warming observed over the last 50 years is
    attributable to human activities (WG I)
  • Global losses in weather related natural
    disasters have increased ten-fold from the 1960s
    to the 1990s, and that a portion of this increase
    must be due to increases in frequency and
    intensity of some extreme events. (WG II)
  • most of the opportunities to reduce emissions
    will come from energy efficiency gains and in
    reducing release of greenhouse gases from
    industry (WG III)

193
Goals of Kyoto Protocol
  • Reduction of greenhouse gases to below 1990
    levels
  • 5.2 world wide reduction on average by
    2008-2012
  • 6 for Canada by 2008-2012
  • When sufficient countries ratify the Protocol (at
    least 55 countries comprising at least 55 of
    emissions), Protocol comes into effect
  • USA - 25 of emissions

194
Kyoto Emissions Agreement
195
Source Gregg Marland and Tom Boden (CDIAC, Oak
Ridge National Laboratory).
196
Greenhouse Effect - Conclusion
  • Since 1700, humans have directly or indirectly
    caused the concentration of the major greenhouse
    gases to increase
  • Scientists predict that this increase may enhance
    the greenhouse effect making the planet warmer by
    0.3 to 0.6 degrees Celsius

197
Cost of Regular Gasoline
  • 3.80 Great Britain
  • 3.80 The Netherlands
  • 3.74 Italy
  • 3.69 Belgium
  • 3.62 France
  • 3.57 Germany
  • 3.20 Japan
  • 1.39 United States
  • in U.S. dollars as of October 13, 1997

198
History of Global Warming
  • 1904 Swedish scientist Svante Arrhenius was,
    according to NASA, "the first person to
    investigate the effect that doubling atmospheric
    carbon dioxide would have on global climate."

199
History of Global Warming
  • Arrhenius began studying rapid increases in
    anthropogenic carbon emissions, determining
    that "the slight percentage of carbonic acid in
    the atmosphere may, by the advances of industry,
    be changed to a noticeable degree in the course
    of a few centuries."

200
History of Global Warming
  • The unique research of Arrhenius suggested that
    this increase could be beneficial, making Earth's
    climates "more equable" and stimulating plant
    growth and food production. Until about 1960,
    most scientists thought it implausible that
    humans could actually affect average global
    temperatures.

201
History of Global Warming
  • 1950s Geophysicist Roger Revelle, with the help
    of Hans Suess, demonstrated that carbon dioxide
    levels in the air had increased as a result of
    the use of fossil fuels.

202
History of Global Warming
  • 1965 Serving on the President's Science Advisory
    Committee Panel on Environmental Pollution in
    1965, Roger Revelle helped publish the first
    high-level government mention of global warming.
    The book-length report identified many of the
    environmental troubles the nation faced, and
    mentioned in a "subpanel report" the potential
    for global warming by carbon dioxide.

203
History of Global Warming
  • 1977 "In 1977 the nonpartisan National Academy
    of Sciences issued a study called Energy and
    Climate, which carefully suggested that the
    possibility of global warming 'should lead
    neither to panic nor to complacency.'

204
History of Global Warming
  • Rather, the study continued, it should 'engender
    a lively sense of urgency in getting on with the
    work of illuminating the issues that have been
    identified and resolving the scientific
    uncertainties that remain.'

205
History of Global Warming
  • As is typical with National Academy studies, the
    primary recommendation was for more research."
    From "Breaking the Global-Warming Gridlock" by
    Daniel Sarewitz and Roger Pielke Jr., THE
    ATLANTIC, July 2000

206
History of Global Warming
  • Roger Revelle chaired the National Academy Panel,
    which found that about forty percent of the
    anthropogenic carbon dioxide has remained in the
    atmosphere, two-thirds from fossil fuel and
    one-third from the clearing of forests. It is now
    known that carbon dioxide is one of the primary
    greenhouse gases that contributes to global
    warming and remains in the atmosphere for a
    century.

207
History of Global Warming
  • 1980s Representative Al Gore (D-TN), who had
    been a student of Revelle's, co-sponsored the
    first Congressional hearings to study the
    implications of global warming and to encourage
    the development of environmental technologies to
    combat global warming.

208
History of Global Warming
  • 1982 Roger Revelle published a widely-read
    article in SCIENTIFIC AMERICAN addressing the
    rise in global sea level and the "relative role
    played by the melting of glaciers and ice sheets
    versus the thermal expansion of the warming
    surface waters."

209
History of Global Warming
  • 1983 The Environmental Protection Agency
    released a report detailing some of the possible
    threats of the anthropogenic emission of carbon
    dioxide.

210
History of Global Warming
  • 1988 NASA climate scientist James Hansen and his
    team reported to Congress on global warming,
    explaining, "the greenhouse warming should be
    clearly identifiable in the 1990s" and that "the
    temperature changes are sufficiently large to
    have major impacts on people and other parts of
    the biosphere, as shown by computed changes in
    the frequency of extreme events and comparison
    with previous climate trends."

211
History of Global Warming
  • With the increased awareness of global warming
    issues, the Intergovernmental Panel on Climate
    Change (IPCC) was established by the World
    Meteorological Organization and the United
    Nations Environment Programme to assess
    scientific, technical and socio-economic
    information relevant for the understanding of
    climate change, its potential impacts and options
    for adaptation and mitigation. The IPCC was the
    first international effort of this scale to
    address environmental issues.

212
History of Global Warming
  • 1990 Congress passed and President George Bush
    signed Public Law 101-606 "The Global Change
    Research Act of 1990. The purpose of the
    legislation was "to require the establishment of
    a United States Global Change Research Program
    aimed at understanding and responding to global
    change, including the cumulative effects of human
    activities and natural processes on the
    environment, to promote discussions towards
    international protocols in global change
    research, and for other purposes."

213
History of Global Warming
  • As part of the Act, the Global Change Research
    Information Office (GCRIO) was established "to
    disseminate to foreign governments, businesses,
    and institutions, as well as citizens of foreign
    countries, scientific research information
    available in the United States which would be
    useful in preventing, mitigating, or adapting to
    the effects of global change. The office began
    formal operation in 1993.

214
History of Global Warming
  • 1992 In June of 1992, over 100 government
    leaders, representatives from 170 countries, and
    some 30,000 participants met in Rio de Janeiro at
    the U.N. Conference on Environment and
    Development (UNCED or the "Earth Summit").

215
History of Global Warming
  • There, an international assembly formally
    recognized the need to integrate economic
    development and environmental protection into the
    goal of sustainable development.

216
History of Global Warming
  • 1997 In December, 1997, more than 160 nations
    met in Kyoto, Japan, to negotiate binding
    limitations on greenhouse gases for the developed
    nations, pursuant to the objectives of the
    Framework Convention on Climate Change of 1992.

217
History of Global Warming
  • The outcome of the meeting was the Kyoto
    Protocol, in which the developed nations agreed
    to limit their greenhouse gas emissions, relative
    to the levels emitted in 1990. The United States
    agreed to reduce emissions from 1990 levels by 7
    percent during the period 2008 to 2012.

218
History of Global Warming
  • 1997 In December, 1997, more than 160 nations
    met in Kyoto, Japan, to negotiate binding
    limitations on greenhouse gases for the developed
    nations, pursuant to the objectives of the
    Framework Convention on Climate Change of 1992.

219
History of Global Warming
  • The outcome of the meeting was the Kyoto
    Protocol, in which the developed nations agreed
    to limit their greenhouse gas emissions, relative
    to the levels emitted in 1990.
  • The United States agreed to reduce emissions from
    1990 levels by 7 percent during the period 2008
    to 2012.

220
History of Global Warming
  • Also that year, the United States Senate
    unanimously passed the Hagel-Byrd Resolution
    notifying the Clinton Administration that the
    Senate would not ratify any treaty that would (a)
    impose mandatory greenhouse gas emissions
    reductions for the United States without also
    imposing such reductions for developing nations,
    or (b) result in serious harm to our economy.

221
History of Global Warming
  • 2001 The IPCC released its third assessment
    report, concluding on the basis of "new and
    stronger evidence that most of the observed
    warming over the last 50 years is attributable to
    human activities." They also observed that "the
    globally averaged surface temperature is
    projected to increase by 1.4 to 5.8 degrees
    Celsius over the period 1990 to 2100."

222
History of Global Warming
  • The same year, President George W. Bush announced
    that the United States would not ratify the Kyoto
    Protocol. The Protocol is now in limbo until one
    of the two crucial holdouts Russia or the
    United States will ratify the treaty.

223
History of Global Warming
  • 2003 Senator John McCain (R-AZ) and Senator
    Joseph Lieberman (D-CT) co-sponsored a proposal
    for mandatory caps on "greenhouse gas" emissions
    from utilities and other industries.

224
History of Global Warming
  • Although the proposal was rejected in the Senate
    by a margin of 55 to 43, it was the Senators'
    first attempt to garner Senate attention for the
    issue of global warming, and McCain and Lieberman
    were encouraged by the support for the measure.
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